1. Field of the Invention
The present invention relates generally to a water-cooling device, and more particularly to a water-cooling device, which has higher heat dissipation performance and is free from the problem of overheating of the internal stator assembly.
2. Description of the Related Art
A conventional water-cooling thermal module includes a heat sink made of copper or aluminum with good thermal conductivity. One side of the heat sink is directly attached to a heat generation component such as a central processor for absorbing the heat generated by the central processor. The other side of the heat sink transfers the heat to a cooling fluid in the water-cooling thermal module. The heat exchange efficiency of such structure is not good. This is because the heat exchange or heat dissipation area between the heat sink and the cooling fluid is too small. When the cooling fluid quickly flows through the radiating fins of the heat sink, the cooling fluid can hardly carry away the heat absorbed by the radiating fins. In order to eliminate this shortcoming, multiple column bodies or flow ways are disposed on one side of the heat sink to enlarge the heat exchange or heat dissipation area between the heat sink and the cooling fluid. However, the heat dissipation performance can be only slightly enhanced and the effect is still poor. As a result, the heat can be hardly effectively dissipated and the heat dissipation efficiency is poor.
Moreover, in operation of the pump unit of the conventional water-cooling module, the stator assembly will generate heat. In addition, the stator assembly must be isolated from the cooling fluid. Therefore, the stator assembly itself can be only air-cooled to dissipate the heat. Such cooling effect is poor. Accordingly, it often takes place that the stator assembly burns out due to overheating. The problem of overheating of the stator assembly will shorten the lifetime of the water-cooling module.
Also, in the conventional water-cooling module, in order to protect the stator assembly of the pump unit from damage due to contact with the cooling fluid, the stator assembly is positioned on outer side of the water-cooling module, while the rotor assembly for driving the cooling fluid to circulate within the water-cooling module is positioned inside the water-cooling module corresponding to the stator assembly. The magnetization between the stator assembly and the rotor assembly takes place through the housing of the water-cooling module so as to operate the rotor assembly. In consideration of sufficient structural strength, the housing of the water-cooling module must have a certain thickness. Therefore, the rotor assembly and the stator assembly are spaced from each other by a considerable distance due to the thickness of the housing. This will affect the operation efficiency of the pump unit. As a result, as a whole, the heat dissipation performance of the water-cooling module will be deteriorated.